Myiasis is a disease caused by dipterous larvae infesting live human or vertebrate animals (Zumpt, 1965). Besides, myiasis not only cause damage, but it also can help people to solve some medicine and forensic medicine problem. Because some myiasis producers also occur on animal wounds and corpses, larvae will eat necrotic tissue to help wounds heal. And forensic specialists can determine the time of death by larvae of flies (Nigam et al. 2006; Vanin et al. 2008). So they have great significance in medicine and forensic medicine as well. It is generally found in human beings and domestic animals (Hall and Wall, 1995; Singh and Singh, 2015). Myiasis agents mainly include larvae of Oestridae, Calliphoridae, Sarcophagidae, and Muscidae (Zumpt, 1965; Hall and Wall, 1995; Pezzi et al. 2019), which has caused major economic obstacle to animal husbandry (Zumpt, 1965; Francesconi and Lup, 2012). However, myiasis is rarely recorded in wild animals due to their being relatively easily hunted or seeking shelters (Hall, 1991; Hall et al., 2016).
In domestic artiodactyla ruminants such as cattle and sheep, myiasis is very common, which can lead to the death of animals and cause great economic losses (Farkas et al. 1997; Hall, 1997; Francesconi and Lup, 2012; Islam et al. 2015). Wild animals are also susceptible to myiasis due to wound infection by parasitic fly larvae. For example, Huang et al (2016) and Yan et al (2019) found that Przewalski's Horse (Equus ferus przewalskii) (Poliakov, 1881) was highly susceptible to gastric myiasis in the Kalamaili Nature Reserve (KNR) and Xinjiang Research Centre for Breeding Przewalski's Horse, Xinjiang, China. The traumatic myiasis was caused by Wohlfahrtia magnifica (Diptera: Sarcophagidae) (Schiner, 1862). In the 20th century, musk deer (Moschus spp.) cutaneous myiasis was reported in the Sikhote-Alin Mountains, caused by Booponus inexpectatus (Diptera: Calliphoridae) (Grunin, 1947) forming subcutaneous warbles (Rognes, 1998). However, there has been no evidence of myiasis of wild forest musk deer (Moschus berezovskii) in the captive population at present. The forest musk deer we studied are mainly distributed in eastern Asia, especially China. Although they are currently the most abundant musk deer species in China, they are rarely seen in the wild. It has been listed in CITES appendix Ⅱ and is an endangered animal on the IUCN Red List. Furthermore, it is an important resource animal because adult males secrete musk with high medicinal, economic, and cultural value. At present, captivity is the main strategy for the conservation of forest musk deers (Wang and Sheng, 1988; Yang et al. 2003; Meng et al. 2006).
On July 6, 2019, we found a case of myiasis of forest musk deer in Fengchun Musk Deer Breeding Center. The myiasis of forest musk deer was found to be traumatic. Traumatic myiasis is mainly caused by fly larvae developing in animal decaying tissue after female flies directly laying eggs/larvae at the open wounds of human or animals, resulting in the host wound and surrounding skin to appear swelling, inflammation, pain, and other health problems (Noutsis and Millikan, 1994; Hall, 1997; Yan et al. 2019). Diagnosis and prevention of myiasis are extremely important because myiasis threatens the host health and causes significant economic losses to the livestock industry. At present, the pathogen species of myiasis is mainly diagnosed by morphological and molecular data, sometimes by monoclonal antibody-based enzyme-linked immunosorbent assay (MAb-ELISA) (Azeredo-Espin and Lessinger, 2006; Severini et al. 2015; Pezzi et al. 2015). Herbert et al (2003) suggested that DNA barcodes can be used to identify species, and some Lucilia genus are difficult to morphological identify (Sonet et al, 2012), so we collected larvae and eggs from the wound and fur of the injured forest musk deer for DNA identification. Results showed that the pathogen of myiasis of forest musk deer was the Lucilia caesar (Diptera: Calliphoridae) (Linnaeus, 1758). Since a large number of parasites can seriously affect the host's health and even death, we should pay more attention to the wound healing of forest musk deer and reduce the occurrence of myiasis.